TY - THES

T1 - Development of hard coatings for press hardening processes

AU - Maringer, Christian

N1 - embargoed until 06-06-2016

PY - 2011

Y1 - 2011

N2 - The increasing energy prices during the last decade boosted the lightweight design in automotive industry. One result of these developments is to use high strength steels e.g. USIBOR® 1500. Such steel sheets are formed in press hardening processes where especially an enhanced adhesive wear is present. In this thesis, hard coatings within the system Cr-Si-N are investigated with the focus to reduce the adhesive wear during press hardening processes. Therefore, Cr-Si-N coatings with Silicon contents up to 17.5 at% (on the metal sublattice) were deposited by physical vapour deposition using arc evaporation. Detailed investigations of the coatings prepared concentrate on structure, morphology, hardness, residual stress and thermal stability as a function of their Si content. The thermal stability tests include structure, mechanical properties and oxidation characterization after annealing in vacuum and ambient atmosphere at 400 °C and 800 °C. Furthermore the friction and wear behaviour was investigated by ball on disk tests at room temperature and 800 °C. Additional to these investigations special application near measurements on an OPTIMOL® SRV tester and Hardware tests were conducted.

AB - The increasing energy prices during the last decade boosted the lightweight design in automotive industry. One result of these developments is to use high strength steels e.g. USIBOR® 1500. Such steel sheets are formed in press hardening processes where especially an enhanced adhesive wear is present. In this thesis, hard coatings within the system Cr-Si-N are investigated with the focus to reduce the adhesive wear during press hardening processes. Therefore, Cr-Si-N coatings with Silicon contents up to 17.5 at% (on the metal sublattice) were deposited by physical vapour deposition using arc evaporation. Detailed investigations of the coatings prepared concentrate on structure, morphology, hardness, residual stress and thermal stability as a function of their Si content. The thermal stability tests include structure, mechanical properties and oxidation characterization after annealing in vacuum and ambient atmosphere at 400 °C and 800 °C. Furthermore the friction and wear behaviour was investigated by ball on disk tests at room temperature and 800 °C. Additional to these investigations special application near measurements on an OPTIMOL® SRV tester and Hardware tests were conducted.

KW - Cr-Si-N

KW - Presshärten

KW - adhäsiver Verschleiß

KW - Struktur

KW - Morphologie

KW - Härte

KW - Eigenspannung

KW - Oxidation

KW - Lichtbogenverdampfung

KW - Cr-Si-N

KW - press hardening

KW - adhesive wear

KW - structure

KW - morphology

KW - hardness

KW - residual stress

KW - oxidation behaviour

KW - arc evaporation

M3 - Diploma Thesis

ER -